Environmental Evolution:
Effects of the Origin and Evolution of Life on Planet Earth

Lynn Margulis, Clifford Matthews + Aaron Haselton (editors)

Environmental Evolution is used as a textbook, but it is a reader rather
than a structured work, with thirteen papers on a broad range of topics.
These tend towards the "big picture", the inter-disciplinary (on the
boundaries between traditional life and earth sciences), and in a few
cases the controversial. The result is a collection which should have
something for anyone at all interested in evolution.

My favourite paper is a study of microbial landscapes by Stjepko Golubic.
This describes the ecology of microbe-populated sabkha (salt flats)
and the stromatolites produced by their sedimentation and fossilization.
Particularly provoking was a diagram of the kind usually used to show
floral variation with elevation — here showing microbial variation over
an elevation change of metres, between low and high tide levels.

Paul K. Strother and Elso S. Barghoorn look at fossil evidence from
the Archean eon, starting with uncontroversial fossils from around 2
billion years ago and then using that in the interpretation of possible
fossils from as far back as 3.4 billion years. Michael McElroy compares
the atmospheres of Earth, Venus, and Mars, highlighting how radically
the presence of life has changed the Earth's atmosphere from where it
would otherwise be. And Tony Swain surveys the function and evolution
in plants of semiochemicals such as phenols, terpenoids, and alkaloids.

Among the papers with controversial elements are James Lovelock's 1973
paper "The Gaia Hypothesis" and a paper by Clifford Matthews arguing
that hydrogen cyanide polymers were precursors in the formation of
the first proteins and nucleic acids. And Lynn Margulis writes about
symbiosis in the origin of protists, both the now accepted symbiotic
origins of mitochondria and chloroplasts (which she helped to establish)
and the still undecided case for a relationship between undilipodia
and spirochetes.

Two chapters tackle topics in the history of science: Antonio Lazcano
glances at early ideas about the origins of life, looking at Oparin
and Herrera as well as Miller and Urey, and Raymond Siever sketches a
history of plate tectonics. Other contributions include papers on the
origins of membrane structure (David Deamer), the Ediacaran fauna (Mark
McMenamin), environmental pollution by inorganic chemicals (Jonathan
King), and karyotypic fission in mammalian evolution (Neil Todd).